Runner wheel for turbines, etc.



V. KAPLAN RUNNER WHEEL FOR 'IURBINES, ETC

Sept. 23 1924.

Filed Sept. 1,

lt eteiited Septfiil, i'irlild.

1,509,.tidll micron KAPLAN, oneness, CZECHOSLQVAKIA.

RUNNER WHEEL TUE-BIKES, ETC.

.llppllcetion filed September '1, 1921. Serial No. 497,748.

To all whom may concern:

Be it known that l, Vrorou KAPLAN, a citizen of the-State oi Csechoslovelzie, residing at the Deutsche 'lechnische Hool t schule, et ldrumi, Czechoslovakia, have in? vented certain new and useful Improvements in Runner l li'heels for Turbines, Etc. (for which l heye applied for Letters Patent in l isiuee, den. 25, 1921; ltiily, Jen. 1d,}.l921; Sweden, Dec. 23, i920; l lorwey, llremtfiritsin, Jun. 10, 1921; Austria, Jan. 2, i918; Germeny, Dec. 13, 1919; Czechoslovakia, dune 19%),1oi which the following is u specificstion.

The unners heretofore used for water turbines, centrifugal-pumps, end the like, lieve large inlet angles, and elsocomperetiuelyffjlergeoutlet angles. Therefore, in orderto properly deflect the weter flowing through the runners, either many short bledes', or few long bledes are required. in both cases the surteces wetted by the liquid s.ie,.,;lerge, which means at large resistance resulting" in e lowering of. the eficiency.

According to my invention, I avoid this drewbscle by melting, the outlet angles, or, es the cause may be, the inlet angles, at least for the greeter pert of the blade surface, smaller then one-eighth oi the inlet and outlet angles respectively measured on the eppertaining stream lines, and by melting the ores. of ell the blades smaller then one end one-helif times the ores of that surface of revolution, generated by the rotation of the runner inlet or outlet edge ebout the runner ems.

l em'ewere, that there are runners, which have as computed with the blade length, s large blade pitch, but only for the purpose of avoiding the usual channel-shape between the blades, as purpose which is neither de sired nor utteined by myinvention.

in the enueued drawing, in which a. runner embodying my invention is illustrated for water turbines, Fig. 1 is a. section through the ieft-hond hall of a runner for radial admission; Fig. 2 is e diagram of two adjacent blade surfaces having the stream surface s--s in Fig. 1, Fig. 3 is a. section through the left-hand hell of a runner for axial admission, and Fig. 4 e diegram of two adjacent blade surfaces having the stream surface s-s in Fig. 3. Fig. 5 lo a. section of a runner for admission inclined relative to the runner axis, while Fig. 6 is e diegrem of two adjacent blade surthat this expedient in itself, would only be feces heving'tlie stream line 8 -s in Fig. 5. The runner according to Fig. 1 is similar to that of a. slow-speed Francis turbine. The shape and relative position of the blade sur feces however differ considerably, as indicated by the diagram, Fig. 2. Compared with the inlet angle 5, which is made large foi hydreulic reasons, the outlet angle 8 is made very smell, being as small as about 5' one-eighth of the inlet angle {3. Due to the shepe giventhe blade surfaces as shown, the water would be so excessively deflected,

e disadvantage. But, if at the same time, the (if size or the number of the blade surfaces is decreased below the usual size or number, as for instance, by making the wetted blade urea smaller then one and one-halt times the urea of that surface of revolution that can be generated by therotetion of the runner inlet edge H Figs. 1, 3, 5, ebouttlie runner exis z-e, then the whole amount of water flowing through the runner only exper'iences that mean deflection, which some 515'? sponds' to the required hydraulic conditions. This same mean deflection therefore is achieved with either shorter or fewer blades, end necessarily with lessfriction, than with the heretofore" customary arrangement oi blodes. By means oisuch e flIIlNLlllCtlOn, not only is thus the eiliciency iii sensed, but itrequired, the specific number of icvolm tions can be reduced-below the limits here to'lore reached.

The condition above referred to, to wit, that the outlet angle 8 relating to the some stream-line,- be at the most equal to one-- eighth of the inlet angle (5 can be carried out either for the entire blede surface, 01 for the greater part of the same. 'llhese angles are supposedto be determined by the tangents t (Figs. 2,4 and 6) at the ends of that centre blade-section'line (01-O!) which can be drawn at equal distenceirom the l section-lines of blade-face and bludebacli.

Of course, the outlet angle t cen be con siderebly reduced below one-eighth of the inlet angle, if required. The diagram, ljig'. at shows, for instance, the blade-sections of e runner for uniel admission (Fig. 3), the, outlet angle 6 of which is zero, at least in the section with the stream surface. e e. But the edmissioiu above described of the outlet angle can, be successfully carried through even below zero, if" the wetted blade surface is reduced below the limit indicated used in the case of all other -In such cases, the outlet angle 8 becomes negative, as shown by the diagram, Fig. 6.- Fig. 5 shows, the vertical projection ot the runner appertainin to these blade sections, the admission of. w ich therefore is inclined relative to the runner axis z-z. According to the accepted view, the use of such small outlet angles is not permissible but thisview cannot be maintained, if one limits the size of the wetted blade surface accordingto my invention. On the other hand, the use of such blade sections is not restricted to the shapes of runners and the t 'pes of admission shown in the drawing. n the contrary; such sections can also he runners, the flow of which takes place in orderly streammrfaees.

The area of a bladev surface S (Figs. 1, 3 and 5) which I will refer to as f can be taken from the blade-dia ram of a runner, or from the finished mode of the same, supthat the surface of the blade-back 1' Figs. 4 and 6, be the basis of all further a; entation. As is well-known, the area (I of that surface of rotation, that is rated by the rotation of the runner int edge e--e (Figs. 1, 3 and 5) about the runner axis z--z,, can be determined by Guldins rule. If, therefore, the runner has n blades, a, wheel constructed according to my invention must meet the following conditions: Kg and nf 3/2 F, of which the former condition must be fulfilled at least along the greater part of. the bladesurface. y I

.That my invention does not avold the Of course, a runner, constructed accordmg to my-invention must have a roperly constructed guiding element for mission,

and care must be taken to maintain a corresponding amount of energy by the use of suitable suction-pipes.

I claim as my invention:

In a runner for water turbines cen-' and the like, bladessod shaped that t e inlet or outlet angle for trifugal pum the greater art of the blade surface is less than ,;th 0? the outlet and inlet angle respectiv'ely, measured on the appertaining stream-lines, and that the total blade area is less than 1 times the area of the surface of revolution generated by the rotation of the runner inlet or outlet edge around the runner axis.

In testimony whereof I afiix my signature in presence of two witnesses.

VICTOR KAPLANQ Witnesses:

HARIANNE KNY. D. HUTTELEY. 

